How to set cursor location, pivot_point in script?
See Adhi's answer here as to why this won't work the way you are doing it.

Using Context
It's easier to read 3D View space's settings through bpy.context,
e.g.:

Use bpy.context.space_data, if the 3D View area is active (i.e. accessed through an operator executed from the 3D View itself).
Use bpy.context.area.spaces[1], if accessed through a Console whose display type is directly switched from a 3D View.
Use bpy.context.screen.areas[X].spaces[0] if accessed through a Console in another area, index X must be searched beforehand.


What you want to use is
bpy.context.area.spaces[1].pivot_point='CURSOR'
bpy.context.area.spaces[1].cursor_location = (0.0, 0.0, 0.0)

For the cursor location, there is a shorter alternative. All 3D View's cursor location is linked to the scene's, so it can also be accessed from bpy.context.scene:
bpy.context.scene.cursor_location = (0.0, 0.0, 0.0)

V2.8+ :
bpy.context.scene.cursor.location = (0.0, 0.0, 0.0)